A collaborative team from the UCSF AIDS Health Project, the UCSF Center for AIDS Prevention Studies, and the San Francisco Department of Public Health proposes a three-year, randomized, controlled trial of a single-session counseling intervention designed to change the behavior of men at greatest risk of HIV: those who continue to engage in high-risk sex with men and who repeatedly test for HIV. HIV incidence among such men-individuals who had tested three or more times-was almost triple that of all other testers in San Francisco. The intervention helps individuals identify and re-evaluate their "self-justifications," that is, the thoughts, attitudes, or beliefs present in their minds when they engage in unprotected anal sex. Following a successful study of this approach, in which the team employed mental health professionals to conduct the intervention, the team now wishes to test the efficacy of the intervention when performed by paraprofessional counselors as an integral part of the risk assessment component of HIV antibody counseling ("pre-test counseling"). To accomplish this, 300 men will be recruited when they call to schedule an anonymous HIV antibody test. Participants must report unprotected anal insertive or receptive sex with a non-primary partner in the prior 12 months, and three or more previous HIV tests. Participants will be randomized to the intervention group (enhanced pre-test counseling) or control group (standard pre-test counseling) and will complete follow-up interviews at 6 and 12 months. The primary outcome measure will be change in the number of episodes of unprotected anal sex with non-primary partners. Participant satisfaction with pre-test counseling will also be measured and compared between the groups. This study will answer a practical question: can this theory-based, single-session counseling intervention, conducted by trained paraprofessional counselors, result in reduced risk among a group of high-risk men? An affirmative answer will have immediate implications for improving the effectiveness of HIV counseling nationwide and potentially reducing transmission of HIV.